"We shall take every opportunity to continue to say clearly and loudly 'not in our name' and 'not for our faith,' " a coalition of imams and organizations representing British Muslims wrote in a letter cited by The Observer.
The imams added that the use of the title “jihadis” to describe ISIL members gives credibility to militants and amounts to a slur to the Islamic faith.
Signatories to the letter to David Cameron, including Sughra Ahmed, president of the Islamic Society of Britain, called for the prime minister to reassess his own language.
Cameron, in common with other senior politicians, has repeatedly made reference to the Islamic State during his public announcements, including a Commons debate this month.
Signatories also included Mohammed Abbasi, from the Association of British Muslims, and Amjad Malik QC, president of the Association of Muslim Lawyers.
"We do not believe the terror group responsible should be given the credence and standing they seek by styling themselves Islamic State. It is neither Islamic, nor is it a state,” they wrote.
Asserting that the so-called Islamic State lacked any acceptance with Muslims or the international community, they suggested using “UnIslamic State” to refer to the group.
"The group has no standing with faithful Muslims, nor among the international community of nations. It clearly will never accept the obligations that any legitimate state has, including the responsibility to protect citizens and uphold human rights,” the Muslim coalition wrote.
"So we believe the media, civic society and governments should refuse to legitimize these ludicrous caliphate fantasies by accepting or propagating this name.
“We propose that 'UnIslamic State' (UIS) could be an accurate and fair alternative name to describe this group and its agenda – and we will begin to call it that," they added.
Powerful Message
Admitting that British Muslims need to do more to dissuade their young men from joining ISIL, the signatories of the letter said that their letter sent a powerful message that UK Muslims reject ISIL.
"We believe that it would send a powerful message in Britain and around the world if you would join us, as our prime minister, in leading a national debate to seek a suitable alternative way to refer to this group and further challenge its legitimacy and influence,” the signatories added.
"This could be especially powerful because everybody at home and abroad can see that you are being asked to do so by British Muslims themselves who want to be clear about why this group is so vehemently rejected.
"We are sure that most British Muslims would agree that 'UnIslamic State' is a considerably more fitting label for this poisonous group – and hope that our fellow citizens will join us in that.
"We know that this would be one small, symbolic step and that we must all work together to build the inclusion and integration in British society that would repel these poisonous ideas."
Source: On Islam